#pragma ident "$Id$"

#ifndef GPSTK_SP3_SATID_HPP
#define GPSTK_SP3_SATID_HPP

//============================================================================
//
//  This file is part of GPSTk, the GPS Toolkit.
//
//  The GPSTk is free software; you can redistribute it and/or modify
//  it under the terms of the GNU Lesser General Public License as published
//  by the Free Software Foundation; either version 2.1 of the License, or
//  any later version.
//
//  The GPSTk is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU Lesser General Public License for more details.
//
//  You should have received a copy of the GNU Lesser General Public
//  License along with GPSTk; if not, write to the Free Software Foundation,
//  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
//
//  Copyright 2004, The University of Texas at Austin
//
//============================================================================

//============================================================================
//
//This software developed by Applied Research Laboratories at the University of
//Texas at Austin, under contract to an agency or agencies within the U.S.
//Department of Defense. The U.S. Government retains all rights to use,
//duplicate, distribute, disclose, or release this software.
//
//Pursuant to DoD Directive 523024
//
// DISTRIBUTION STATEMENT A: This software has been approved for public
//                           release, distribution is unlimited.
//
//=============================================================================

#include <iostream>
#include <sstream>
#include <iomanip>

#include "Exception.hpp"
#include "SatID.hpp"

/**
 * @file SP3SatID.hpp
 * gpstk::SP3SatID - navigation system-independent representation of a satellite
 * as defined by the SP3 specification.
 */

namespace gpstk
{
class SP3SatID : public SatID
{
public:

    /// empty constructor, creates an invalid object
    SP3SatID() throw()
    {
        id=-1;
        system=systemGPS;
    }

    /// explicit constructor, no defaults, SP3 systems only
    SP3SatID(int p, SatelliteSystem s) throw()
    {
        id = p;
        system = s;
        switch(system)
        {
        case systemGPS:
        case systemGlonass:
        case systemGalileo:
        case systemLEO:
            break;
        // invalidate anything non-SP3
        default:
            system = systemUnknown;
            id = -1;
        }
    }

    /// constructor from string
    SP3SatID(const std::string& str) throw(Exception)
    {
        try
        {
            fromString(str);
        }
        catch(Exception& e)
        {
            GPSTK_RETHROW(e);
        }
    }

    /// cast SatID to SP3SatID
    SP3SatID(const SatID& sat) throw()
    {
        *this = SP3SatID(sat.id,sat.system);
    }

    /// set the fill character used in output
    /// return the current fill character
    char setfill(char c) throw()
    {
        char csave=fillchar;
        fillchar=c;
        return csave;
    }

    /// get the fill character used in output
    char getfill() throw()
    {
        return fillchar;
    }

    // operator=, copy constructor and destructor built by compiler

    /// operator == for SP3SatID
    bool operator==(const SP3SatID& right) const
    {
        return ((system == right.system) && (id == right.id));
    }

    /// operator != for SP3SatID
    bool operator!=(const SP3SatID& right) const
    {
        return !(operator==(right));
    }

    /// operator < (less than) for SP3SatID : order by system, then number
    bool operator<(const SP3SatID& right) const
    {
        if(system==right.system)
            return (id < right.id);
        return (system < right.system);
    }

    /// operator > (greater than) for SP3SatID
    bool operator>(const SP3SatID& right) const
    {
        return (!operator<(right) && !operator==(right));
    }

    /// operator >= (greater than or equal) for SP3SatID
    bool operator>=(const SP3SatID& right) const
    {
        return (!operator<(right));
    }

    /// operator <= (less than or equal) for SP3SatID
    bool operator<=(const SP3SatID& right) const
    {
        return (!operator>(right));
    }

    /// return a character based on the system
    /// return the single-character system descriptor
    /// @note return only SP3 types, for non-SP3 systems return '?'
    char systemChar() const throw()
    {
        switch (system)
        {
        case systemGPS:
            return 'G';
        case systemGalileo:
            return 'E';
        case systemGlonass:
            return 'R';
        case systemLEO:
            return 'L';
        case systemMixed:
            return 'M';
        // non-SP3
        default:
            return '?';
        }
    };

    std::string systemString() const throw()
    {
        switch (system)
        {
        case systemGPS:
            return "GPS";
        case systemGalileo:
            return "Galileo";
        case systemGlonass:
            return "Glonass";
        case systemLEO:
            return "LEO";
        case systemMixed:
            return "Mixed";
        default:
            return "Unknown";
        }
    };

    /// read from string
    /// @note GPS is default system (no or unknown system char)
    void fromString(const std::string s) throw(Exception)
    {
        char c;
        std::istringstream iss(s);

        id = -1;
        system = systemGPS;  // default
        if(s.find_first_not_of(std::string(" \t\n"), 0) == std::string::npos)
            return;                    // all whitespace yields the default

        iss >> c;                     // read one character (non-whitespace)
        switch(c)
        {
        // no leading system character
        case '0':
        case '1':
        case '2':
        case '3':
        case '4':
        case '5':
        case '6':
        case '7':
        case '8':
        case '9':
            iss.putback(c);
            system = SatID::systemGPS;
            break;
        case ' ':
        case 'G':
        case 'g':
            system = SatID::systemGPS;
            break;
        case 'R':
        case 'r':
            system = SatID::systemGlonass;
            break;
        case 'E':
        case 'e':
            system = SatID::systemGalileo;
            break;
        case 'L':
        case 'l':
            system = SatID::systemLEO;
            break;
        case 'M':
        case 'm':
            system = SatID::systemMixed;
            break;
        default:                   // non-SP3 system character
            Exception e(std::string("Invalid system character \"")
                        + c + std::string("\""));
            GPSTK_THROW(e);
        }
        iss >> id;
        if(id <= 0)
            id = -1;
    }

    /// convert to string
    std::string toString() const throw()
    {
        std::ostringstream oss;
        oss.fill(fillchar);
        oss << systemChar()
            << std::setw(2) << id;
        return oss.str();
    }

private:

    static char fillchar;  ///< fill character used during stream output

}; // class SP3SatID

/// stream output for SP3SatID
inline std::ostream& operator<<(std::ostream& s, const SP3SatID& sat)
{
    s << sat.toString();
    return s;
}

} // namespace gpstk

#endif
